Point $P$ is $2\mathrm{.}75{10}^{-4}m$ from a small metal sphere A with a negative charge of $2\mathrm{.}98{10}^{-8}C.$ A second sphere, $B$ with a positive charge of $4\mathrm{.}89{10}^{-6}C$ also contributes to the field. See diagram below. Note that the angle $=62\mathrm{.}6.$

a$)$ Determine the number of excess electrons on sphere $A$ Number

b$)$ Determine the net electric field at $P.$ at a standard angle of $-$

c$)$ Determine the magnitude of the electric field at a point midway between A and $B($and in line with them$)$

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